The ground is common on both fans and leads into the main harness plug.
The hot for one fan and the common ground goes right to the main harness.
The wires at the relay are as follows:

A - orange from main harness (guessing main power for second fan)
B - tan from main harness (guessing relay switched power)
C - black/red stripe for second fan (12V to second fan)
D - green/white stripe from main harness (guessing temp sending wire to relay)

Now, should there not be another relay for the other fan? From what I understand one fan was ECM controlled and the other strictly off of a temp sensor - was the second relay mounted elsewhere on a stock Camaro for whatever reason? Are my assumptions correct on the above wiring? Better yet, anyone have a diagram of the factory fan wiring diagram from a dual fan TPI car?

 

revised my original post for a little more clarity...

I think I may be on the right track. Can anyone verify whether there was a second relay for the other fan mounted elsewhere in the harness/on the car? I would assume there was a relay for both fans...

 

Anyone know how the factory fans are wired? I keep coming across a set of diagrams here but that does not match the fans I have.

I would really prefer not to have to buy a Haynes manual just for a single wiring diagram.


EDIT: Got some diagrams off the Monte board - please disregard thread

 

I'm not sure if this helps but on my '87 both fan relays are right next to each other in front of the battery.

 

Are they both wired on the same side of the 6-pin connector though? The fan side of my harness (which looks the same as the one 92blue sells) contains only the two fan plugs, one relay plug, then of course the main 6-pin plug. The other relay must be wired in on the engine side of the harness.

 

I've been looking into the variations on the fan wiring throughout the years for a while now. I know atleast some (perhaps all) the firebird TPI harnesses have the fan wiring incorporated into the harness, its not removable. Also, they have both fan relays located near each other by the fans. The Camaros had the removable fan harness which contained one relay, and the second relay was by the firewall. Atleast thats my understanding from digging up used harnesses throughout the years.

 

Thanks for that rundown - so I have a Camaro harness. Very strange how they differed between Camaros and Firebirds...

 

ON my '91 Camaro TPI, here's what I have found out:

There are 2 relays right beside each other on the driver's side firewall. The

Primary fan wire colors are:
green/white - ECM
Org - hot
black/red - fan
brown - gen

Aux fan wire colors:
grey - temp switch in passenger head
org - hot
black/pink - fan
brown - gen

I ran down the info off of this diagram for my year:

http://www.autozone.com/az/cds/en_us...3d801eef19.jsp

 

Thanks for the info nikkev

I think I have decided to go with an aftermarket variable speed controller - a little pricier, but its a simpler install, less components and a few benefits over an on/off factory type setup.